In humans, the respiratory tract, with an area of a football field is the largest surface connecting the body with the outside world required for sufficient exchange of air; meanwhile, it is affected by many physical, chemical, and biological substances in the air to cause disorders including asthma, chronic obstructive pulmonary disease, inflammatory conditions of the lung and respiratory tract. Also, some genetic disorders such as cystic fibrosis are affected by the respiratory tract's connection with the outside world. Viruses and bacteria may enter the body and cause infections in the respiratory tract to occur.
Cough is one of the common conditions that needs to be treated. However, the currently available treatments are only limited in symptom relief leaving the body to recover by itself and in many cases the recoveries are sluggish.
In Australia, the sale of cough syrup is over $20 million a year. It is estimated that the worldwide market of cough syrup exceeds $1 billion per annum.
Persistent cough sometimes with period of normality lasting for months or even years is attributed to bronchial asthma, occult reflex, or post viral/bacterial infections and smoking causing the airway to become hypersensitive/hyperreactive. Accordingly there is a need for an efficient treatment that can assist the body to recover after it has been affected by many physical, chemical, and biological substances in the air that can cause disorders in the respiratory system.
The discussion of documents, acts, materials, devices, articles and the like is included in this specification solely for the purpose of providing a context for the present invention. It is not suggested or represented that any or all of these matters formed part of the prior art base or were common general knowledge in the field relevant to the present invention as it existed before the priority date of each claim of this application.